The present invention is generally directed to cooling systems, and more particularly, to a cooling system employing a heat exchanger with thermoelectric structures disposed between adjacent tubes thereof for enhanced cooling of heat generating components in, for example, an electronic device such as a mainframe computer or other electronic system requiring cooling.
As is well known, as the circuit density of electronic chip devices increases in order to achieve faster and faster processing speed, there is a correspondingly increasing demand for the removal of heat generated by these devices. The increased heat demand arises both because the circuit devices are packed more closely together and because the circuits themselves are operated at increasingly higher clock frequencies. Nonetheless, it is also known that runaway thermal conditions and excessive heat generated by chips is a leading cause of failure of chip devices. Furthermore, it is anticipated that the demand for heat removal from these devices will increase indefinitely. Accordingly, it is seen that there is a large and significant need to provide useful cooling mechanisms for electronic circuit devices.
The use of large thermoelectric cooling elements is known. These elements operate electronically to produce a cooling effect. By passing a direct current through the legs of a thermoelectric device, a temperature difference is produced across the device which may be contrary to that which would be expected from Fourier""s Law.
At one junction of the thermoelectric element both holes and electrons move away, toward the other junction, as a consequence of the current flow through the junction. Holes move through the p-type material and electrons through the n-type material. To compensate for this loss of charge carriers, additional electrons are raised from the valence band to the conduction band to create new pairs of electrons and holes. Since energy is required to do this, heat is absorbed at this junction. Conversely, as an electron drops into a hole at the other junction, its surplus energy is released in the form of heat. This transfer of thermal energy from the cold junction to the hot junction is known as the Peltier effect.
Use of the Peltier effect permits the surfaces attached to a heat source to be maintained at a temperature below that of a surface attached to a heat sink. What these thermoelectric modules provide is the ability to operate the cold side below the ambient temperature of the cooling medium (air or water). When direct current is passed through these thermoelectric modules a temperature difference is produced with the result that one side is relatively cooler than the other side. These thermoelectric modules are therefore seen to possess a hot side and a cold side, and provide a mechanism for facilitating the transfer of thermal energy from the cold side of the thermoelectric module to the hot side of the module.
Although the use of cooling systems with heat exchangers is known, there continues to be a need for further enhanced cooling of circuit devices considering the ever increasing processing speeds and space constraints.
The shortcomings of the prior approaches are overcome, and additional advantages are provided, by the present invention which in one aspect comprises a heat exchanger using thermoelectric structures to facilitate cooling of an electronic device. Moreover, it should be understood that a heat exchanger in accordance with the present invention is not limited to cooling electronic devices, but rather, has many applications such as, for example, cooling heat generating mechanical components. For simplicity, the following discussion of a heat exchanger in accordance with an aspect of the present invention is focused on cooling electronic devices, with the understanding that it may be employed in other applications as well.
In one embodiment, the heat exchanger comprises one or more pairs of adjacent spaced passages. The adjacent spaced passages are in fluid communication with an input port of the heat exchanger and are configured to carry a cooling fluid received through the inlet port. The heat exchanger further includes a cooling subsystem configured to remove heat from one or more pairs of the adjacent spaced passages. The cooling subsystem has at least one thermoelectric structure, which is disposed between at least one pair of the adjacent spaced passages.
In another aspect, a heat exchange made in accordance with an aspect of the present invention may be part of a cooling system. The cooling system may include a heat transfer device, which is configured to remove heat from a heat generating component. The input port of the heat exchanger is in fluid communication with the heat transfer device of the cooling system.
In a further aspect, a method of fabricating a heat exchanger for cooling a heat generating component is provided. This method includes: providing one or more pairs of adjacent spaced passages, the adjacent spaced passages being in fluid communication with an input port and being configured to carry a cooling fluid; and disposing a cooling subsystem between at least one pair of the one or more pairs of adjacent spaced passages, the cooling subsystem being configured to remove heat from one or more of the adjacent spaced passages, the cooling subsystem comprising at least one thermoelectric structure.
Various additional enhanced structures and methods are also described and claimed hereinbelow.
Advantageously, by using thermoelectric structures or modules integrated with a heat exchanger comprising part of a fluid-based cooling system, the overall heat removal capability at a given temperature for a given volume and volumetric air flow through the heat exchanger is enhanced.
Additional features and advantages are realized through the techniques of the present invention. Other embodiments and aspects of the invention are described in detail herein and are considered part of the claimed invention.